Please help:).

Part (a)

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Work Shown:

In step 2, I divided both sides by 3. In step 4, I subtracted 2 from both sides. In step 6, I multiplied both sides by 7.

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Part (b)

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Work Shown:

The steps are fairly similar to part (a). The steps were

since proposition states that a number is greater than 25, if is true then the number must actually be greater than 25.

this implies that all possible options, except 24, can be accepted